DE102020101991B4 - Power supply unit and electrical machine with such a power supply unit - Google Patents

Abstract

The invention relates to a power supply unit (200) for an electrical machine. The power supply unit (200) comprises: a plurality of line sections (211a-n); a first machine-front power electronic circuit with a plurality of half bridges (201a-n) which is designed to apply a respective current to the plurality of line sections (211a-n); and a second machine rear line electronic circuit having a plurality of bidirectional switches (203aa-nn). The second electronic circuit on the back of the machine has a matrix topology and is designed to connect each of the plurality of line sections (211a-n) via a plurality of current paths which are defined by the plurality of bidirectional switches (203aa-nn) and combinations thereof to connect other line sections (211a-n) in an electrically conductive manner.

Description

The invention relates to a power supply unit for an electrical machine, in particular an electrical motor, and an electrical machine with such a power supply unit.

From the DE102014118356A1 an electrical machine is known which differs from other electrical machines by the structure of the stator winding in that solid conductor rods are provided in the stator instead of classic windings. All these wire rods on the back of the electrical machine are short-circuited on one side with the help of a short-circuit ring and extend in the axial direction parallel along the stator (the front of an electrical machine or an electrical motor is defined here as the side on which the output shaft or the A-side; accordingly, the side on which the B-side is located is defined here as the rear of the electric machine or the electric motor). Such a design of a stator is in 1 shown, with a first stator section 101 a housing (or a stator core) 103 comprising a plurality of slots 105a defined, and a second stator section 107 a variety of solid line rods 111a includes, which at their rear ends via a short-circuit ring 109 are conductively connected to one another and with their front ends in each case in the grooves 105a of the housing 103 of the first stator section 101 are introduced.

On the front of the in the not provided with a short-circuit ring DE102014118356A1 The electrical machine described are the conductor bars 111a connected to a power electronic circuit comprising a plurality of half bridges. The power electronics on the front of the electrical machine allow a current flow with the desired shape over the conductor bars 111a to be imprinted. This enables both the number of phases and the number of pole pairs in the DE102014118356A1 to change the electrical machine described during operation. This is why this electrical machine is also known as a vario-phase machine (also known as a cage stator machine).

A further training from the DE102014118356A1 known electrical machine is in the DE102014114615A1 described in which by connecting a further power electronic circuit to the rear of the electrical machine, which the in 1 shown short-circuit ring 109 replaced, the number of degrees of freedom of this electrical machine can also be increased. However, in order to impress a sinusoidal current curve, for example, the power electronics on the back of the from the DE102014114615A1 known electrical machine are switched accordingly often, ie with the frequency of the sinusoidal current curve.

Further power supply units for an electrical machine are from the WO2017 / 127557A1 and the DE102005032965A1 known.

Against this background, the object of the present invention is to provide an improved power supply unit for an electrical machine and such an electrical machine.

The present invention is based on the knowledge to design the power electronic circuit for the rear of the machine with a matrix topology. Here, bidirectional switches are provided for each line rod for the connection to all other line rods. In this way, the line rods can be permanently connected for a fixed operating point on the rear of the machine. The bidirectional switches only need to be activated when switching the number of phases or pole pairs. This significantly reduces the switching frequencies of the power electronics and thus also the switching losses on the rear of the machine. In addition, this connection has a very high degree of freedom compared to already known topologies, since the bars can be connected to one another as required.

Thus, according to a first aspect, the object is achieved by a power supply unit for an electrical machine, the power supply unit comprising: a plurality of line sections; a first machine-front power electronic circuit with a plurality of half bridges, which is designed to apply a respective current to the plurality of line sections; and a second power electronic circuit on the back of the machine with a plurality of bidirectional switches. The second power electronic circuit on the rear of the machine has a matrix topology and is designed to connect each of the plurality of line sections to all other line sections in an electrically conductive manner via a plurality of current paths, which are defined by the plurality of bidirectional switches and combinations thereof. Due to the matrix topology of the second power electronics circuit on the back of the machine, a first line section (i) can be connected to a second line section via a first bidirectional switch, (ii) can be connected to a third line section via a second bidirectional switch and (iii) via the first bidirectional switch and a third bidirectional switch connectable to the third line section.

According to one embodiment, the matrix topology of the second power electronics circuit on the back of the machine corresponds to a matrix in which matrix elements on the main diagonal of the matrix and matrix elements below or above the main diagonal of the matrix correspond to a respective bidirectional switch.

According to a further embodiment, due to the matrix topology of the second power electronic circuit on the back of the machine, the first line section (i) can be connected to a fourth line section via a fourth bidirectional switch, (ii) can be connected to the fourth line section via the first bidirectional switch and a fifth bidirectional switch, ( iii) connectable to the fourth line section via the first bidirectional switch, the third bidirectional switch and a sixth bidirectional switch and (iv) connectable to the fourth line section via the second bidirectional switch and the sixth bidirectional switch.

The power supply unit can furthermore comprise a DC voltage source which can be connected in an electrically conductive manner in parallel to the plurality of half bridges of the first power electronic circuit on the front of the machine in order to apply a respective current to the line sections.

Furthermore, the power supply unit can comprise a control unit which is designed to switch each of the plurality of bidirectional switches of the second power electronic circuit on the rear of the machine. The control unit for controlling the bidirectional switches can include at least one charge pump driver.

According to one embodiment, the control unit is designed to change a switching state of at least one other bidirectional switch of the second power electronic circuit on the rear of the machine in the event of a malfunction of a bidirectional switch in order to maintain the operation of the power supply unit.

According to a further embodiment, the multiplicity of line sections comprises a multiplicity of parallel-arranged line rods which are introduced into slots of a stator core in order to form a stator of the electrical machine. The line rods can be evenly distributed in the circumferential direction of the stator core. The power supply unit can furthermore comprise a multiplicity of potential rings which are designed to connect the multiplicity of conductor bars to the multiplicity of bidirectional switches.

According to a further embodiment, the power supply unit comprises n line sections and at least m bidirectional switches, wherein: $$m=\frac{n^2-\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="DE102020101991B4\_0005.png,DE102020101991B4\_0008.png"\; state="\{\{state\}\}">n</figure-callout>}}{2}.$$

The bidirectional switches can include oppositely connected IGBTs in parallel without free audio diodes. Likewise, the bidirectional switches can also include MOSFETs connected in series in opposite directions. In the following, the bidirectional switches are therefore sometimes also referred to as bidirectional semiconductor switches. The bidirectional switches can be designed in bare die format.

According to a second aspect of the invention, an electric machine, in particular an electric motor with a power supply unit according to the first aspect of the invention described above, is provided.

Thus, by connecting power electronics with a matrix topology on the rear side of the electrical machine, embodiments of the invention make it possible to interconnect the line sections with one another as desired. It is sufficient to switch the power electronics by means of the control unit only when the operating mode of the electrical machine (phases, number of pole pairs or other operating modes) is changed. This reduces switching losses and provides an electrical machine with a higher number of degrees of freedom.

• 1 eine Explosionsdarstellung von Komponenten eines Stators einer herkömmlichen elektrischen Maschine;
• 2 eine schematische Darstellung einer Stromversorgungseinheit für eine elektrische Maschine gemäß einem Ausführungsbeispiel mit einer leistungselektronischen Schaltung an der Vorderseite und einer leistungselektronischen Schaltung mit Matrixtopologie an der Rückseite der elektrischen Maschine;
• 3 eine Draufsicht sowie eine Seitenschnittansicht der Anordnung einer Vielzahl von bidirektionalen Schaltern zum Ausbilden einer leistungselektronischen Schaltung mit Matrixtopologie an der Rückseite einer elektrischen Maschine gemäß einem Ausführungsbeispiel;
• 4 eine Draufsicht sowie eine Seitenschnittansicht der Anordnung einer Vielzahl von bidirektionalen Schaltern zum Ausbilden einer leistungselektronischen Schaltung mit Matrixtopologie an der Rückseite einer elektrischen Maschine gemäß einem weiteren Ausführungsbeispiel;
• 5 ein Balkendiagram, welches die Abhängigkeit der Anzahl der bidirektionalen Halbleiterschalter zum Ausbilden einer leistungselektronischen Schaltung mit Matrixtopologie an der Rückseite einer elektrischen Maschine von der Anzahl der Leitungsstäbe gemäß einem Ausführungsbeispiel illustriert;
• 6a eine schematische Darstellung einer Stromversorgungseinheit für eine elektrische Maschine gemäß einem Ausführungsbeispiel mit einer leistungselektronischen Schaltung an der Vorderseite und einer leistungselektronischen Schaltung mit Matrixtopologie an der Rückseite der elektrischen Maschine;
• 6b ein Diagramm, welches unterschiedliche Arbeitsbereiche einer elektrischen Maschine mit der Stromversorgungseinheit von 6a für unterschiedliche Polpaarzahlen zeigt;
• 6c ein Diagramm, welches die Verteilung der Phasen und der Stromrichtungen in den Leitungsstäben der Stromversorgungseinheit von 6a zeigt;
• 6d die Stromversorgungseinheit von 6a mit einer anderen Verschaltung der bidirektionalen Schalter der leistungselektronischen Schaltung mit Matrixtopologie zur Kompensation des Ausfalls eines bidirektionalen Schalters;
• 7a eine schematische Darstellung einer Stromversorgungseinheit für eine elektrische Maschine gemäß einem weiteren Ausführungsbeispiel mit einer leistungselektronischen Schaltung an der Vorderseite und einer leistungselektronischen Schaltung mit Matrixtopologie an der Rückseite der elektrischen Maschine;
• 7b ein Diagramm, welches unterschiedliche Arbeitsbereiche einer elektrischen Maschine mit der Stromversorgungseinheit von 7a für unterschiedliche Polpaarzahlen zeigt;
• 7c ein Diagramm, welches die Verteilung der Phasen und der Stromrichtungen in den Leitungsstäben der Stromversorgungseinheit von 7a zeigt;
• 8a eine schematische Darstellung einer Stromversorgungseinheit für eine elektrische Maschine gemäß einem weiteren Ausführungsbeispiel mit einer leistungselektronischen Schaltung an der Vorderseite und einer leistungselektronischen Schaltung mit Matrixtopologie an der Rückseite der elektrischen Maschine;
• 8b ein Diagramm, welches unterschiedliche Arbeitsbereiche einer elektrischen Maschine mit der Stromversorgungseinheit von 8a für unterschiedliche Polpaarzahlen zeigt; und
• 8c ein Diagramm, welches die Verteilung der Phasen und der Stromrichtungen in den Leitungsstäben der Stromversorgungseinheit von 8a zeigt.

The invention is described in more detail below with reference to exemplary embodiments and the figures. In the figures show:

• 1 an exploded view of components of a stator of a conventional electrical machine;
• 2 a schematic representation of a power supply unit for an electrical machine according to an embodiment with a power electronic circuit on the front side and a power electronic circuit with a matrix topology on the rear side of the electric machine;
• 3 a plan view and a side sectional view of the arrangement of a plurality of bidirectional switches for forming a power electronic circuit Matrix topology on the rear side of an electrical machine according to an exemplary embodiment;
• 4th a plan view and a side sectional view of the arrangement of a multiplicity of bidirectional switches for forming a power electronic circuit with a matrix topology on the rear side of an electrical machine according to a further exemplary embodiment;
• 5 a bar diagram which illustrates the dependency of the number of bidirectional semiconductor switches for forming a power electronic circuit with a matrix topology on the rear side of an electrical machine on the number of conductor bars according to an exemplary embodiment;
• 6a a schematic representation of a power supply unit for an electrical machine according to an embodiment with a power electronic circuit on the front side and a power electronic circuit with a matrix topology on the rear side of the electric machine;
• 6b a diagram showing different working areas of an electrical machine with the power supply unit of 6a shows for different numbers of pole pairs;
• 6c a diagram showing the distribution of the phases and the current directions in the conductor bars of the power supply unit of 6a shows;
• 6d the power supply unit of 6a with a different interconnection of the bidirectional switches of the electronic power circuit with a matrix topology to compensate for the failure of a bidirectional switch;
• 7a a schematic representation of a power supply unit for an electrical machine according to a further embodiment with a power electronic circuit on the front side and a power electronic circuit with a matrix topology on the rear side of the electric machine;
• 7b a diagram showing different working areas of an electrical machine with the power supply unit of 7a shows for different numbers of pole pairs;
• 7c a diagram showing the distribution of the phases and the current directions in the conductor bars of the power supply unit of 7a shows;
• 8a a schematic representation of a power supply unit for an electrical machine according to a further embodiment with a power electronic circuit on the front side and a power electronic circuit with a matrix topology on the rear side of the electric machine;
• 8b a diagram showing different working areas of an electrical machine with the power supply unit of 8a shows for different numbers of pole pairs; and
• 8c a diagram showing the distribution of the phases and the current directions in the conductor bars of the power supply unit of 8a shows.

In the following detailed description, reference is made to the accompanying figures, which form a part hereof, and in which there is shown, by way of illustration, specific embodiments in which the invention may be carried out. It goes without saying that other embodiments can also be used and structural or logical changes can be made without deviating from the concept of the present invention. The following detailed description is therefore not to be taken in a limiting sense. Furthermore, it goes without saying that the features of the various exemplary embodiments described herein can be combined with one another, unless specifically stated otherwise.

The aspects and embodiments of the present invention are described with reference to the figures, wherein like reference characters generally refer to like elements. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more aspects of the present invention.

2 shows a schematic representation of an embodiment of a power supply unit 200 for an electric machine. According to one embodiment, the electric machine can be an electric motor for driving a drive shaft, for example. As in 2 shown includes the power supply unit 200 a DC voltage source 202 which is connected to a first power electronic circuit or power electronics on the front of the electrical machine. In this case, the first power electronics can according to one of the in the DE102014118356A1 Be designed embodiments described, to which reference is hereby made in full.

The in 2 The illustrated embodiment comprises the first electronic power circuit on the front of the electrical machine a plurality of half bridges, in particular semiconductor switches 201a-n , which parallel with the voltage source 202 are connected. In an enlarged view are in 2 two possible configurations of a semiconductor switch of the first electronic power circuit shown on the front side of the electrical machine, here by way of example for the large number of half-switches of the semiconductor switches 201 n. For further details on the structure and functionality of the semiconductor switches 201a-n will turn to the DE102014118356A1 referenced.

As in 2 each is the semiconductor switch 201n on the front of the electrical machine with a respective line section 211a-n tied together. In the representation of 2 are the line sections 211a-n shown as inductors. According to one embodiment, the line sections 211a-n like in the DE102014118356A1 described and in 1 shown as solid line rods 211a-n be formed, which are arranged parallel to one another and extend in the axial direction. Alternatively, the line sections 211a-n Filaments of conductive material include, for example, copper, aluminum or carbon nanotubes. The line sections 211a-n can be arranged in the air gap of the electrical machine, inserted into grooves of the stator and / or introduced into the core of the stator by drilling or die casting. In the following, non-limiting exemplary embodiments are described in which the line sections 211a-n as management staff 211a-n are trained.

The power electronics on the rear side of the electrical machine also include a plurality of bidirectional semiconductor switches which, as described in more detail below, form a circuit with a matrix topology and with the reference numbers 203aa-nn Marked are. Each is a bidirectional semiconductor switch 203aa-nn designed to conduct a current bidirectionally depending on the switching state (ie to conduct a current either in one or the other direction) or to block the current. How the 2 can be seen is due to the switching of the large number of bidirectional semiconductor switches 203aa-nn each of the wire rods in a matrix topology 211a-n each via different current paths, which are through different bidirectional semiconductor switches 203aa-nn and different combinations thereof can be defined with the other wire rods 211a-n electrically conductive connectable.

In an enlarged view are in 2 two possible configurations of a bidirectional semiconductor switch of the second power electronics are shown on the rear of the electrical machine, here as an example for the large number of half-switches of the half-switches 203aa . According to one embodiment, the bidirectional semiconductor switch 203aa Contrastingly parallel-connected IGBTs without free-wheeling diodes. According to a further embodiment, the bidirectional semiconductor switch 203aa Contrasting series-connected MOSFETs include. Special MOSFETs without a freewheeling diode are also suitable for use in the bidirectional semiconductor switch 203aa conceivable.

As in 2 shown, the power supply unit 200 furthermore a control unit 210 comprise, which is formed, the plurality of bidirectional semiconductor switches 203aa-nn the power electronic circuit on the back of the electrical machine. The bidirectional semiconductor switch can be controlled 203aa-nn by means of the control unit 210 via a bus, for example a CAN or I2C BUS.

Da, as described in more detail below, the bidirectional semiconductor switches 203aa-nn according to one embodiment of the invention only when the control unit changes the phases or number of pole pairs 210 must be controlled, according to one embodiment, the bidirectional semiconductor switches 203aa-nn designed to remain in a switching state over a longer period of time. For this purpose, when controlling the bidirectional semiconductor switch 203aa-nn Charge pump drivers ("Chargepump" drivers) are used, which are designed as bidirectional semiconductor switches 203aa-nn to be controlled over a longer period of time, ie to leave it in the same switching state.

As already described above and as in 2 can be seen, defines the power electronic circuit with the multitude of bidirectional semiconductor switches 203aa-nn a matrix topology or matrix structure. The bidirectional semiconductor switches are in this matrix topology 203aa-nn such with each other and with the conductor bars 211a-n interconnected that each wire rod of the plurality of wire rods 211a-n via different current paths, which are through different bidirectional semiconductor switches 203aa-nn and different combinations thereof are defined with all other wire rods of the plurality of wire rods 211a-n can be connected in an electrically conductive manner.

For example, in 2 the first line rod 211a via the bidirectional semiconductor switch 203aa with the second line rod 211b , via the bidirectional semiconductor switch 203ba with the third lead rod 211c , via the bidirectional semiconductor switch 203 approx with the fourth lead rod 211d and via the bidirectional semiconductor switch 203na with the nth conduction rod 211n electrically conductive connectable. Next to these connections of the first line rod 211a with the others Management rods 211b-n there are, however, due to the arrangement and interconnection of the large number of bidirectional semiconductor switches 203aa-nn a large number of other possible connections or current paths between the line rods 211a-n . For example, there is another connection between the first line rod 211a and the third lead rod 211c via the bidirectional semiconductor switch 203aa and the bidirectional semiconductor switch 203bb . Since, as already described above, the control unit 210 is formed, each of the bidirectional semiconductor switches 203aa-nn to lock or to close in one or the other direction, can by means of the control unit 210 different combinations of the multitude of bidirectional semiconductor switches 203aa-nn can be selected in the power electronic circuit with matrix topology in order to create different connections or current paths between the conductor bars depending on the application 211a-n define.

In the 2 shown interconnection of the plurality of bidirectional semiconductor switches 203aa-nn defines a matrix topology, each with a bidirectional semiconductor switch 203aa-nn is formed on the diagonal of the matrix and below it, ie the second letter index either corresponds to the first letter index or is a letter which is in the alphabet before the first letter index. Although the in 2 illustrated matrix topology to a preferred embodiment of the interconnection of the plurality of bidirectional semiconductor switches 203aa-nn is, other matrix topologies are also conceivable, for example matrix topologies in which further bidirectional semiconductor switches are also arranged and interconnected above the matrix diagonals.

In the 3 and 4th are two exemplary embodiments for a practical implementation of the in 2 shown second power electronic circuit with matrix topology on the rear of the electrical machine, in each case in the form of a front view and a lateral cross-sectional view. For the sake of clarity, here is an example with four line rods 211a-d have been chosen, which extend parallel in the axial direction and are arranged in the circumferential direction at an angular distance of 90 °.

How yourself 3 can be seen, is in this embodiment, the line rod 211a connected directly to a potential ring (or potential hollow cylinder) 213a and via the bidirectional semiconductor switch 203aa with a potential ring 213b tied together. Between the potential ring 213a and the potential ring further inside 213b there is an isolation ring. With the potential ring 213c and the potential ring 213d is the management staff 211a not connected in this embodiment.

The management staff 211b is directly with the potential ring 213b connected and via the bidirectional semiconductor switch 203ba with the potential ring 213c tied together. Between the potential ring 213b and the potential ring further inside 213c there is an isolation ring. With the potential ring 213a and the potential ring 213d is the management staff 211b not connected in this embodiment.

The management staff 211c is directly with the potential ring 213c tied together. Further is the line rod 211c via the bidirectional semiconductor switch 203bb with the potential ring 213a and via the bidirectional semiconductor switch 203cc with the potential ring 213d tied together. Between the potential ring 213c and the potential ring further inside 213d there is an isolation ring. With the potential ring 213b is the management staff 211c not connected in this embodiment.

The management staff 211d is directly with the potential ring 213d tied together. Further is the line rod 211d via the bidirectional semiconductor switch 203 approx with the potential ring 213a and via the bidirectional semiconductor switch 203cb with the potential ring 213b tied together. With the potential ring 213c is the management staff 211d not connected in this embodiment.

In the 4th The embodiment shown differs from that in FIG 3 illustrated embodiment in the specific design of the electrically conductive connection of the respective line rod 211a-d with the bidirectional semiconductor switches 203aa-cc which in turn with the potential rings 213a-d are electrically connected. In both embodiments, the respective line rod is at the machine-rear end 211a-d a connecting web is formed, for example the connecting web 220a on the back of the machine end of the wire rod 211c , which over the connecting element 215c as described above, directly to the potential ring 213c is electrically connected and directly or indirectly electrically conductive with the respective bidirectional semiconductor switches 203bb , 203cc connected is. At the in 3 The embodiment shown is, for example, the connecting web 220a via a respective further connecting element 220b respectively. 220c with the bidirectional semiconductor switch 203bb respectively. 203cc electrically connected. At the in 4th The embodiment shown is the connecting web 220a directly with the bidirectional semiconductor switch 203bb , which in turn is electrically conductive with the potential ring 213a is connected, and the bidirectional semiconductor switch 203cc electrically connected, which in turn is electrically conductive with the potential ring 213d connected is.

5 illustrates the number of bidirectional semiconductor switches 203aa-nn of the second power electronic circuit with matrix topology on the rear of the electrical machine depending on the number of conductor bars 211a-n for the in 2 illustrated embodiment. As shown, the in 2 The illustrated embodiment shows the number of bidirectional semiconductor switches m with the number of wire rods n according to the following relationship: $$m=\frac{n^2-\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="DE102020101991B4\_0005.png,DE102020101991B4\_0008.png"\; state="\{\{state\}\}">n</figure-callout>}}{2}.$$

Since in the embodiment of 2 with an increasing number of line rods 211n the number of bi-directional semiconductor switches 203aa-nn according to the in 5 dependency shown increases, is offered in an electrical machine with a large number of wire rods 211a-n the use of space-saving bidirectional semiconductor switches 203aa-nn in bare die format. Such semiconductor switches in bare die format can save space with the wire rods 211an be connected, for example to the above in connection with the 3 and 4th described manner.

In the following, exemplary embodiments are described in which the power supply unit 200 for example twelve line rods 211a-l and according to the in 5 dependency shown 66 bidirectional semiconductor switches 203aa-kk . For the sake of clarity, the 6a , 6d , 7a and 8a showing the respective interconnections of the twelve wire rods 211a-l with the 66 bidirectional semiconductor switches 203aa-kk illustrate with matrix topology, not all semiconductor switches 203aa-kk marked with a reference number. However, those skilled in the art will be based on the reference numerals used in these figures and in the 2 illustrated systematics of the matrix topology shown the reference numbers of the unmarked bidirectional semiconductor switch 203aa-kk can easily deduce. As already described above and how this is the 6a , 6d , 7a and 8a can be seen defines the interconnection of the multitude of bidirectional semiconductor switches 203aa-kk a matrix topology in which, according to one embodiment, one semiconductor switch in each case 203aa-kk is formed on the diagonal of the matrix and below it, ie the second letter index either corresponds to the first letter index or is a letter which is in the alphabet before the first letter index.

For this embodiment of the power supply unit 200 with twelve management rods 211a-l and 66 bidirectional semiconductor switches 203aa-kk can the 6a (analogous to the 2 ) the interconnection of the bidirectional semiconductor switches 203aa-kk with matrix topology. At the in 6a The embodiment shown is the control unit 210 (in 6a not shown) of the power supply unit 200 formed the bidirectional semiconductor switch 203aa-kk to switch in such a way that the electrical machine with three phases in the in 6b marked working area can be operated with a low number of pole pairs p ₁ , in which high speeds can be achieved with low torques. For example, the electrical machine can be operated in three further working areas with larger numbers of pole pairs p ₂ , p ₃ and p ₄ , as shown below using the example of the number of pole pairs p ₂ in connection with the 7a-c is described.

6c shows for this embodiment the distribution of the three phases as well as the respective current direction over the conductor bars 211a-l . How the 6c can be removed, flows, for example, through the first line rod 211a (Line rod "1") and the second line rod 211b (Line rod "2") the current with phase U into the power electronics of the power supply unit on the back of the machine 200 into it.

In 6a is shown how the current is based on an exemplary circuit of the large number of bidirectional semiconductor switches 203aa-kk by the control unit 210 flows through the power electronics on the back of the machine with matrix topology. How does the 6a can be seen, the in 6c The exemplary distribution of the current directions and phases U, W and V shown can be achieved in that the bidirectional semiconductor switch 203fa , 203gb, 203hc and 203id by the control unit 210 are switched in a first current direction and the bidirectional semiconductor switches 203je and 203kf are switched in the opposite current direction (the remaining bidirectional semiconductor switches are in a switching state in which they do not conduct any current).

In 6d is shown as the one in 6a Power supply unit shown 200 can compensate for a failure of a switched, ie current-carrying bidirectional semiconductor switch, specifically for example a failure of the bidirectional semiconductor switch 203fa . The control unit 210 the power supply unit 200 is formed, in this case previously by the bidirectional semiconductor switch 203fa running current path between the first line rod 211a (Management stick “1”) and the seventh management stick 211g (Wire rod "7") through a new current path between the first wire rod 211a (Management stick “1”) and the seventh management stick 211g (Line rod "7") to be replaced. As in 6d shown, the new current path between the first line rod 211a (Management stick “1”) and the seventh management stick 211g (Wire rod “7”) can be formed by the control unit 210 the bidirectional main conductor switch 203aa and controls the bidirectional main conductor switch 230fb in such a way that they conduct the current in the first current direction (ie the previous current direction of the semiconductor switch to be compensated) 203fa ).

the 7a-c show (analogous to the 6a-c ) Another example of an arrangement and interconnection of the large number of bidirectional semiconductor switches 203aa-kk the power electronics of the power supply unit on the back of the machine 200 . The in 7a The example shown is the control unit 210 the power supply unit 200 formed the bidirectional semiconductor switch 203aa-kk to switch in such a way that the electrical machine with three phases in the in 7b marked work area can be operated with the number of pole pairs p ₂ , which is greater than the number of pole pairs p _{1 of} the in the 6a-d The example shown is and thus allows higher torques at lower speeds as an example. In 7c is again the distribution of the current directions and phases over the line rods 211a-l shown. How does the 7a can be seen, the in 7c The exemplary distribution of the current directions and phases U, W and V shown can be achieved in that the bidirectional semiconductor switch 203 approx , 203db, 203ig and 203jh by the control unit 210 are switched in a first current direction and the bidirectional semiconductor switches 203ec and 203ki are switched in the opposite current direction (the remaining bidirectional semiconductor switches are in a switching state in which they do not conduct any current).

the 8a-c show (analogous to the 6a-c and 7a-c ) Another example of an arrangement and interconnection of the large number of bidirectional semiconductor switches 203aa-kk the power electronics of the power supply unit on the back of the machine 200 . The in 8a The example shown is the control unit 210 the power supply unit 200 formed the bidirectional semiconductor switch 203aa-kk to switch in such a way that the electric machine has 6 phases (instead of the 3 phases in the 6a-d example shown) in the in 8b marked working area can be operated with the number of pole pairs p _1. In 8c is again the distribution of the current directions and the 6 phases over the line rods 211 al shown. How does the 8a can be seen, the in 8c The exemplary distribution of the current directions and six phases shown can be achieved in that the bidirectional semiconductor switches 203fa, 203gb, 203hc and 203id are controlled by the control unit 210 are switched in a first current direction and the bidirectional semiconductor switches 203je and 203kf are switched in the opposite current direction (the remaining bidirectional semiconductor switches are in a switching state in which they do not conduct any current).

Embodiments of the invention thus enable the conductor bars by connecting power electronics with a matrix topology to the rear of the electrical machine 211a-n to be interconnected as required. It is sufficient to control the power electronics by means of the control unit 210 only switch when the operating mode of the electrical machine (phases, number of pole pairs or other operating modes) is changed. This reduces switching losses and provides an electrical machine with a higher number of degrees of freedom.

Claims (14)

Power supply unit (200) for an electrical machine, with: a plurality of line sections (211a-n); a first power electronic circuit on the front of the machine with a plurality of half bridges (201a-n) which is designed to apply a respective current to the plurality of line sections (211a-n); and a second machine rear power electronic circuit with a plurality of bidirectional switches (203aa-nn), wherein the second machine rear power electronic circuit has a matrix topology and is formed, each of the plurality of line sections (211a-n) via a plurality of current paths, which through the plurality of bidirectional switches (203aa-nn) and combinations thereof are defined to be electrically connected to all other line sections (211a-n), where due to the matrix topology of the second power electronics circuit on the back of the machine, a first line section (211a) (i) can be connected to a second line section (211b) via a first bidirectional switch (203aa), (ii) to a third via a second bidirectional switch (203ba) Line section (211c) can be connected and (iii) can be connected to the third line section (211c) via the first bidirectional switch (203aa) and a third bidirectional switch (203bb). Power supply unit (200) according to Claim 1 , the matrix topology of the second power electronic circuit on the back of the machine being defined by a matrix in which matrix elements on the main diagonal of the matrix and Matrix elements below or above the main diagonal of the matrix correspond to a respective bidirectional switch (203aa-nn). Power supply unit (200) according to Claim 1 , the first line section (211a) (i) being connectable to a fourth line section (211d) via a fourth bidirectional switch (203ca), (ii) via the first bidirectional switch (203aa) and a fifth bidirectional switch (203cb) can be connected to the fourth line section (211d), (iii) via the first bidirectional switch (203aa), the third bidirectional switch (203bb) and a sixth bidirectional switch (203cc) to the fourth line section (211d) can be connected and (iv) can be connected to the fourth line section (211d) via the second bidirectional switch (203ba) and the sixth bidirectional switch (203cc). Power supply unit (200) according to one of the preceding claims, wherein the power supply unit (200) comprises a DC voltage source (202), wherein the DC voltage source (202) can be connected in an electrically conductive manner in parallel to the plurality of half bridges (201 an) of the first power electronic circuit on the front of the machine in order to to apply a respective current to the line sections (211a-n). Power supply unit (200) according to one of the preceding claims, wherein the power supply unit (200) further comprises a control unit (210) which is designed to switch the plurality of bidirectional switches (203aa-nn) of the second power electronic circuit on the back of the machine. Power supply unit (200) according to Claim 5 wherein the control unit (210) for controlling the bidirectional switches (203aa-nn) comprises at least one charge pump driver. Power supply unit (200) according to Claim 5 or 6th , wherein the control unit (210) is designed, in the event of a malfunction of a bidirectional switch (203aa-nn), to change a switching state of at least one other bidirectional switch (203aa-nn) of the second power electronic circuit on the back of the machine in order to maintain the operation of the power supply unit (200) to obtain. Power supply unit (200) according to one of the preceding claims, wherein the multiplicity of line sections (211a-n) comprises a multiplicity of parallel-arranged line rods (211a-n) which are introduced into slots of a stator core in order to form a stator of the electrical machine. Power supply unit (200) according to Claim 8 , wherein the wire rods (211an) are evenly distributed in the circumferential direction and the power supply unit (200) further comprises a plurality of potential rings (213a-d) which are formed, the plurality of wire rods (211a-n) with the plurality of bidirectional switches ( 203aa-nn). Power supply unit (200) according to one of the preceding claims, wherein the power supply unit (200) comprises n line sections (211a-n) and at least m bidirectional switches (203aa-nn), wherein: $$m=\frac{n^2-n}{2}.$$

Power supply unit (200) according to one of the preceding claims, wherein at least one of the bidirectional switches (203aa-nn) comprises oppositely parallel IGBTs without free-air diodes. Power supply unit (200) according to one of the preceding claims, wherein at least one of the bidirectional switches (203aa-nn) comprises MOSFETs connected in series in opposite directions. Power supply unit (200) according to one of the preceding claims, wherein one or more of the plurality of bidirectional switches (203aa-nn) are designed in bare die format. Electric machine, in particular electric motor, with a power supply unit (200) according to one of the preceding claims.

Images